corbro general issues and the recommended standards

8/12/2019 Corbro General Issues and the Recommended Standards

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Marek Bielecki

Anna Chmielewska-Wurch

T

Beata Patalan

General issues

and the recommended standards

for corrugated board

and corrugated board packaging

i n f o r m a t i o np a p e r

Authors:


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Specialist revision: Aleksander Klepaczka, Dr. Eng

Stylistic revision: Joanna Wiatroszak, MA

DTP: Tomasz Perek

Covers designed by Jacek Szymaski

Publisher: The Association of Polish Papermakers

Copyright The Association of Polish Papermakers

The Association of Polish Papermakers would like to thank all those,

who contributed to the making of this publication.


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General issues and the recommended standards for corrugated board and corrugated board packaging

3

The Association of Polish Papermakers

The Association of Polish Papermakers (SPP) is a research, engineering and mana-

gement organisation, associating individuals and corporate members active in the pa-per-making and paper-converting industry and its business and scientic environment.

Our mission is to support the development of the papermaking and paper converting

industry in Poland as well as to integrate the community of papermakers.

The Association has four Sections:

Technical Section,

Paper Section,

Corrugated Board Section

Infrastructure Section.

Activities include:

representing SPP vies-a-vis national and local authorities, commercial cham-

bers, business organisations and others;

monitoring changes in the legal system and reviewing documents drafted by

governmental agencies and related to the papermaking industry and its environ-

ment;

analysing the level of supplies of raw materials and components to papermaking

industry;

supporting the recycling of paper, board and paper waste;

keeping track of the Best Available Techniques (BAT) in the paper making and

paper converting industry;

monitoring energy market, including renewable energy;

reviewing amendments to scal regulations and developments in environmental

protection education.

SPP also has its international operations:

membership in international organisations - CEPI (Confederation of European

Paper Industries) and FEFCO (European Federation of Corrugated Board Ma-

nufacturers),

well-established relations with research and technical papermaking organisa-

tions in the world, such as TAPPI (USA), PPTAC (Canada), PITA (United King-

dom), FPEA (Finland), SPCI (Sweden), ZELLCHEMING (Germany), ATIP (Fran-

ce) and IPH (Brussels).


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4

Our Technical Section is composed of individuals and the supporting members. Its

activities include: organisation of conferences, symposia and trainings; publishing;

collecting and publishing historical records, Expert Group.

The SPP Paper Section associates corporations (SPP Supporting Members) pro-

ducers of pulp, paper and board. Among our members there are 13 companies which

together manufacture 80% of the Polish paper and board production. The Paper Section

- assisted by a consulting rm monitors the legislative process in the eld of environ-

mental protection and provides consultancy services on changes of legal regulations

applicable to the paper industry.

The Corrugated Board Section of SPP associates corporations (the Supporting

Members of SPP) producing or converting the corrugated board. Currently there are

16 companies in the Section, which in total produce ca. 82% of the national production

of corrugated board and packagings thereof. The Section is active in the area of com-

mon interest of its Members, including: promotion of the corrugated board containers

and a product which is fully recoverable and environmentally friendly. Within a promo-

tional campaign of packagings made of the corrugated board a special logo has been

designed Paper packaging offers nature friendly quality. The logo in various colours

is protected and used by the Section Members in their promotional campaigns. The

Section also organises trainings for its Members.

The SPP Infrastructure Section groups the following SPP Supporting Members:

academic, training and R&D centres, designing & engineering agencies, commercial

companies, producers of machines and equipment, providers of services for the pa-

permaking and paper-converting industry. The Section supports the Technical Working

Group for Pulp & Paper Production. The Group is working in the amendment of the

reference document concerning the best available techniques in the pulp and paper

industry (BREF). The Group is chaired by one of the SPP experts.


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5

ProfessorWodzimierz SzewczykInstitute of Papermaking & Printing, Technical University of Lodz

Lodz. 28thJune 2011

O P I N I O N

on a paper entitled: The general issues and the recommended standards for

corrugated board and corrugated board packaging written by Marek Bielecki,

Anna Chmielewska-Wurch, Tomasz Damicki, Beata Patalan, Maciej Soma and

Sawomir dziebo.

The corrugated board is the globally most frequently used packaging material

used for the production of both primary and secondary packagings. In volume

terms, this is the largest group of paper products manufactured in Poland. Due to

such features as strength to weight ratio, suitability for marketing purposes, low

transport and storage costs as well as its easy utilisation and/or recycling capaci-

ties, production of corrugated board has promising growth prospects. The growing

interest in this packaging medium results in the increasing demand for informa-

tion on its manufacturing and converting. The rapid technological progress of the

recent decade has been visible both in the manufacturing technology of the corru-

gated board and packagings, and in the construction of machines for their produc-

tion. The increasing range of corrugated products as well as the technical progress

lay down demanding requirements for a continuous refreshment of knowledge in

various technical elds, a know-how which is not commonly available.

The paper entitled The general issues and the recommended standards for cor-

rugated board and corrugated board packaging, is a valuable supplement to the

Polish literature of the subject. The Authors in order to meet the expectations of

the producers and users of the corrugated board have presented in a straightfor-

ward manner the educational material, containing elementary information for the

sector of corrugated board packagings. The publication includes a wide variety

of topics, covering the production cycle of packagings, starting with the materi-


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als, machines and technologies used for the production of the corrugated board,

through the machines and technologies for manufacturing and printing of blanks,

and ending with folding and gluing the packagings.

The paper presents basic parameters of corrugated boards and packagings thereof,

as well as their testing methodology. Moreover the publication contains packag-

ing classication, their application principles and criteria for packagings having

contact with food.

Due to the fact that the Authors represent different professional specialties, at the

same time being a team of experienced and highly valued experts, the paper con-tains useful practical information, which may be used for training of new staff,

both by packaging producers and by their contractors.

The publication is written in the plain Polish language, however frequently we

can nd industry jargon, which is not compatible with the proper Polish nomen-

clature. When presenting the educational content, special attention should be out

to the vocabulary, in order to avoid bad linguistic habits.

Taking into consideration the content of the publication, I can denitely acknowl-

edge that the Authors have achieved their goal, and their work will popularise the

know-how in the area of manufacturing packagings of the corrugated board, both

among the producers and in their business environment.


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Professor Stanisaw Tkaczyk

Research Institute - COBRO Polish Packaging Research & Development

Centre, Warsaw University of Technology

Warsaw, 28th June 2011.

O P I N I O N

on the publication entitled : The general issues and the recommended stan-dards for corrugated board and corrugated board packaging, by Marek Bielecki,

Anna Chmielewska-Wurch, Tomasz Damicki, Beata Patalan, Maciej Soma and

Sawomir Zdziebo.

Packaging materials made of paper and board, including the corrugated board

are among the most frequently used media for collective and unit packagings,

also used for foodstuffs. Thus the users should have knowledge concerning themedium properties, and consequently its adequate application. Therefore it is nec-

essary to understand the requirements of the production process starting with the

raw materials, through the paper and board forming technology, various types of

packagings and nally the logistics of the lled containers.

The authors from the Association of Polish Papermakers have responded to

the industry need and presented an interesting information material in the area in

question.

The paper in details presents the process of the corrugated board production, in-

cluding among others the diagrams of the most frequently used gluers and cor-

rugators.


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Then there is a description of types of packagings made of the corrugated board,

i.e. rolls (reels), different types of boxes (including SRP, FEFCO classication

catalogue) as well as the modern methods of imprints application (markings,

product and marketing information).

A very good idea was to give a clear presentation of the main features and param-

eters of the corrugated board and packagings thereof, together with the testing

methods.

It should also be stressed that special attention has been paid to the packaging

process, adequate stacking on the pallet, storage and relocation by various meansof transportation.

An important element of the reviewed publication is the thorough description

of the standard requirements for the corrugated board packagings, used in the

circulation and production of food which is particularly important (e.g. recent

problems with export of food to the Russian market).

My opinion of the reviewed paper is high. It gives a general overview of the cor-

rugated board production, packagings and their characteristics, and the in-depth

analysis of application opportunities. In the subsequent editions of the publication

I would suggest adding a section on the recycling of the used packagings.

Concluding I recommend as quick as possible publication of the reviewed paper

on a popular packaging material i.e. the corrugated board and various products

made of that medium.

I would like to congratulate the Authors on their interesting presentation of the

analysed area, and I encourage everyone to read the publication.


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Table of contents

The Association of Polish Papermakers............................................................................................ 3

Opinions................................................................................................................................................ 5

1. Introduction...............................................................................................................................10

2. Components used in the manufacturing of corrugated board and packagings.................11

a. Papers .........................................................................................................................................11

b. Corrugating glues........................................................................................................................12

c. Inks ..............................................................................................................................................13

3. Corrugated board......................................................................................................................15

a. Types of corrugated boards ........................................................................................................15

b. Flute proles................................................................................................................................16

4. Technological process of corrugated board production ......................................................18

5. Corrugated board packagings classication......................................................................23

a. Classication according to the packaging construction...............................................................23

b. FEFCO classication...................................................................................................................24c. Special packagings SRP (Self Ready Packaging) ..................................................................... 27

6. Production process of corrugated board packagings ......................................................... 30

a. Production process of slotted-type boxes (RSC) ....................................................................... 30

b. Die-cut packaging production .................................................................................................... 33

c. Offset printing of packagings...................................................................................................... 38

7. Major properties and parameters of corrugated board........................................................ 41

a. Basis weight............................................................................................................................... 41

b. Edge crash test (ECT)................................................................................................................ 41

c. Flat crash test (FCT).................................................................................................................. 42

d. Bursting strength........................................................................................................................ 42

e. Puncture resistance test (PET).................................................................................................. 43f. 4-point bending stiffness............................................................................................................ 43

g. Water absorption (the Cobb test)............................................................................................... 44

h. Moisture content ........................................................................................................................ 45

i. Flexion of corrugated board (atness) ........................................................................................45

j. Colour of corrugated board.........................................................................................................45

8. Major properties and parameters of packagings.................................................................. 46

a. Strength parameters .................................................................................................................. 46

b. Other packaging tests................................................................................................................ 48

c. Dimensioning ............................................................................................................................. 48

d. Tolerances resulting from the technical capacities of the converting machines ........................ 49

9. Packaging, storage and transport standards for packagings............................................. 51

a. Packing ...................................................................................................................................... 51

b. Storage ...................................................................................................................................... 51

c. Transport.................................................................................................................................... 52

10. General introduction to standards for corrugated board packaging used for food.......... 53

a. GMP (Good Manufacturing Practice) and GHP (Good Hygienic Practice) ................................ 53

b. HACCP (Hazard Analysis and Critical Control Points)............................................................... 54

c. PN-EN ISO 22000:2006............................................................................................................. 55

d. BRC (British Retail Consortium)................................................................................................. 55

e. IFS (International Food Standard).............................................................................................. 56

f. Summary.................................................................................................................................... 5611. References ............................................................................................................................... 57


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Introduction1.

The dynamically developing market trends in the broadly understood packaging sec-

tor, new arising customer needs, demand for exible and non-standard actions, as well

as the variety of challenges faced by the corrugated board producers, necessitated the

publication under the auspices of the Polish Association of Polish Papermakers of

an info on standards applied in the sector of the corrugated board and packaging made

of corrugated board. This task has been assigned to a team of experts and producers

of corrugated board packagings. Using their know-how and experience as well as the

best coopetition practice, the team has presented the essential issues of manufactur-

ing and processing of the corrugated board: manufacturing, technology, logistics and

legal requirements applicable to the corrugated board producers.

This paper contains all basic information concerning the raw materials used for the

production of corrugated board, types of produced corrugated boards and packagings,

the process of manufacturing corrugated board and its processing into packagings,

essential parameters of corrugated boards and parameters of packagings made of

corrugated board, and nally the information on requirements for packaging that come

into contact with foods.

This paper is directed both to persons from the corrugated board sector and to their

customers. It may be used as an excellent guide, but also as a basic manual the ABC

for the packaging sector. It should certainly facilitate communication between the twointerested parties packaging producers and their clients.

We are deeply convinced that this paper will not only provide you with the informa-

tion on the recommended standards, but will also add to the technical and technologi-

cal knowledge on the application of the corrugated board and packagings produced

thereof.

We hope you enjoy the text.


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Components used in the manufacturing of corrugated board and packagings2.

a. Papers

The major component for the production of corrugated board is paper. According to

the type of application and their properties, papers used for corrugated board produc-

tion may be divided into two groups:

Papers for at layers liners,

Papers for corrugated layers utings.

Liners depending on their manufacturing process and the component composition

belong to one of the two main groups:

kraftliners,

testliners.

Kraftliners have the best strength parameters among all the liners. They are com-

posed of the cellulose pulp with a slight addition of the recycled bre. Usually the over-

coat is better glued and has a higher smoothness.

Topliner (white kraftliner) is a grade of kraftliner. Its overcoat in most cases is made

of bleached kraft pulp, while the bottom layer of the non-bleached stock. For the

more advanced imprints white coated kraftliners are used the overcoat is mostly

coated with a pigment coating colour.

Testliners are the two-layer papers, most frequently made of 100% recovered

paper. A testliner is a combination of two layers. Such construction enables the use of

kraft pulp for the overcoat, and the recycled bre for the bottom layer. Due to the price

relation between the expensive cellulose mass and the cheaper paper stock, we ob-

serve the contiguous growth of the latter in the testliner recipes. More and more they

are entirely made of the recycled bre. In such cases the overcoat (top layer) is dyed in

order to imitate the colour of the kraft pulp. Similarly to kraftliners, testliners are manu-

factured with the white overcoat of similar whiteness. For the more advanced imprints

the coated testliners are produced, where the overcoat is most frequently coated withthe pigment coating colour.

In addition to the above described regular papers special papers with specic prop-

erties are also applied. These include among others:

wet-strength papers converted to ensure maintaining strength properties after

wetting (PN-P-50000:1992),

fat-tight papers high resistance to fat and grease penetration. Some of these

papers are particularly resistant to the penetration of the above mentioned sub-

stances (PN-P-50000:1992),


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barrier coated papers with a protective layer, e.g. of polyethylene (PE), covering

one or both paper sides (PN-EN 26590-1:1993),

reproof papers ame and/or ignition resistant (PN-P-50000:1992).

Paper for utings aredivided into two groups:

waste based uting (WBF),

semi chemical utings (SC).

WBF is manufactured exclusively of the recycled bre.

In order to improve its mechanical properties of such uting, starch is added to its

structure. This process is popularly described as bonding. It may be carried out in the

stock (i.e. sizing - starch is introduced into the waste paper pulp) or starch may be ad-

ditionally applied on the paper surface (surface sizing).

The semi-chemical uting contains ca. 70% of the semi-chemical pulp, manufac-

tured from hardwood (mostly birch) in the pulping process. The remaining part of this

pulp consists mostly of the recovered paper.

b. Corrugating glues

The most popular glues for bonding the layers of the corrugated board are starch

glues. Their strengths include biodegradation and renewable source of origin.

Major components of the starch glue:

converted or native starch mostly maize or wheat,

caustic soda ,

borax ,

water .

Starch polysaccharide appearing in a granular form in the tissues of certain plants

and composed almost exclusively of alpha-d-glucose radicals (PN-A-74820:1987). In

Europe it is industrially produced mostly of maize and wheat, less frequently of pota-

toes.

Sodium hydroxide (caustic soda) is used to decrease the glue gel point. Crudestarch has a gel point at 75-80oC. Such joint temperature is difcult to obtain in corru-

gation process on the corrugator, also being disadvantageous for the technology, as it

may cause overheating of the recto. Therefore the gel point is decreased to ca. 55C.

Moreover, sodium hydroxide facilitates the penetration of the glue into the paper.

Borax (hydrated sodium tetra borate Na2B

4O

7x10H

2O) stabilizes the glue, reacting

with the cooked starch, improves glue adherence and its penetration into the paper.

Water is a carrier and facilitates the swelling of starch granules.


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c. Inks

Various printing techniques are applied (screen print, offset) in the process of pack-

aging production, however the most popular method is exo printing using exo-

graphic printing inks.

Flexographic printing inks

Typical exographic inks include:

pigments,

binders,

emulsion resins,

dispersion resins,

additives,

water as a solvent.

Pigments form ca. 10% of the ink mass. They provide colour to the printing inks.

Mostly organic pigments are used for the production of the exographic inks. Titanium

dioxide is the most frequently used white pigment.

Binders constitute about 20% of the ink mass. Acrylic resins (derivatives of acrylic

acid) are used as bonding agents in water-based inks. Ink binder is responsible for the

ink utility as well as the scope of application. Compositions of two types of acrylates

are used emulsions and dispersions.

Emulsion resins are soft, exible, have no gloss and are used in inks for the un-

coated papers.

Dispersion resins are hard, fragile, glossy and quick-drying and thus they are used

in inks for coated papers.

Additives form ca. 5% of the ink mass. Depending on the purpose of application

there are:

waxes,

surface-active agents,

antifoam agents

drying retardants or accelerators.

Waxes are used in order to improve ink rub resistance by reducing contact area and

improving slippage. In the exographic inks synthetic waxes (polyethylene) are used.

Surfactants are wetting agents, introduced into the inks in order to reduce the sur-

face tension.This prevents problems with wetting during pigment distribution and print-

ing.


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Antifoam agents in their majority are silicone and fatty acid defoamers.

Drying retardants or accelerators are glycols or higher alcohols delaying ink drying

and improving the bond of polymer particles.

Offset inks

Offset inks due to the printing technology may be divided into the following three

main groups:

inks for sheet printing,

inks for web printing, xation by absorption (cold-set type),

inks for web printing, xation by evaporation of the high-boiling solvent heated

with hot air or ame (heat-set type).

Table 1 shows average compositions (in %) of the above mentioned offset inks.

Ink components Sheet inks Cold-set inks Heat-set inks

Pigments 15-25 20-25 15-25

Resins 25-20 8-12 25-35

Alkyd resins/ drying oils 20-30 0-12 5-15

Mineral oil 20-25 60 25-40

Additives 5-10 1-5 5-10

Table 1. Composition of offset inks (%)

Offset inks, due to the specic printing technology (ink transfer via an intermediate

cylinder offset cylinder) and low ink thickness on a printout (1-2 m), must have high

colour strength and signicant light fastness.

These inks must also have certain hydrophobic properties printing and non-prin-

ting elements of the offset plates are placed in the same plane. Printing elements have

hydrophobic properties, non-printing are hydrophilic. Thus in order to enable the prin-

ting process, ink must not wet the non-printing elements of the form, and it should only

be taken over by the printing elements.


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Corrugated board3.

a. Types of corrugated boards

Corrugated board board made of one or more layers of uted paper, alternatingly

sized with one or more layers of paper facings.

Depending on the number of layers in the corrugated board there are:

Single-faced corrugated boards boards composed of one ply of uted paper

sized to one layer of facing (PN-P-50000:1992) (Fig. 1);

Fig. 1. Single-faced corrugated board

Double-faced corrugated boards boards made of three layers. One ply of uted

paper sized between two layers of facing (PN-P-50000:1992) (Fig. 2);

Fig. 2. Double-faced corrugated board

Double-double corrugated boards boards composed of ve plies. Two uted

layers sized alternatingly between three facings (PN-P-50000:1992) (Fig. 3);

Fig. 3. Double-double corrugated board


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Tree-wall corrugated boards boards composed of seven plies. Three uted lay-

ers sized alternately between four plies of facing (PN-P-50000:1992) (Fig. 4).

Fig. 4. Tree-wall corrugated board

Not as frequent as the above mentioned types but still available are also four and

nine-ply boards.Moreover, there are the following special purpose boards:

hydrophobic boards (moisture proof, with waterproof adhesive),

boards with tape (tear-off or reinforcing tapes),

barrier boards waterproof, greaseproof boards (PN-P-50000:1992) and

others,

preprint boards,

reproof boards (PN-P-50000:1992).

b. Flute proles

Flute prole depends on the type of uters used for the production and it is a cha -

racteristic indicator of the corrugated board. The most frequently used proles include

utes: B, C and E. Moreover, there are corrugated boards with utes: D, K, A, F, G, N,

O. The most important characteristics of the above mentioned proles include:

ute height,

ute pitch,

take-up ratio

Flute height (B) is the vertical base to peak distance of a ute, while the ute pitch

(A) is the horizontal distance between adjacent ute peaks adherent to the same ply.

(Fig. 5).


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Fig. 5. Flute prole

The take-up ratio is dened as the ratio of the length of the non-uted corrugated

medium to the length of the uted web.

These parameters are characteristic for particular types of uters and may differ

between various manufacturers. In most cases parameters are within the ranges pre-

sented in the Table 2 below.

Prole Take-up ratio Height [mm] Pitch [mm]

O 1.14 0.3 1.2

N 1.11 1.8 0.4 0.5 1.8

G 1.17 0.5 1.8

F 1.19 1.28 0.7 0.8 2.4 2.5

E 1.20 1.35 1.1 1.4 3.2 3.7

B 1.26 1.48 2.3 2.8 6.1 6.6

C 1.36 1.56 3.4 4.0 7.4 8.3

A 1.37 1.53 4.1 4.7 8.7 9.5

K 1.50 5.94 11.7

D 1.48 7.38 15.0

Table 2. Flute prole parameters


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Technological process of corrugated board production4.

Corrugated board is produced on the machine colloquially called a corrugator, which

is a sophisticated production line of 100-140 m, composed of a number of mated sub-

assemblies and installations.A corrugator has the following main subassemblies:

single facer,

double backer,

heating and drying section,

longitudinal cutter,

cross cutter,

piler .

In order to start the production of corrugated board, it is necessary in addition to

standard media, such as electricity, water, compressed air to supply heat required

for the sizing process. Generally boilers (gas or oil-red steam generators) are used,

which can generate steam at pressures of up to about 18 bar. Such steam enables the adju-

stment and control of heating of many elements of the corrugator in the range of tem-

peratures reaching even 200oC.

Another component - essential for bonding of paper plies - is a starch glue, which is

usually prepared in the glue preparation plant.

The process of board production starts on the single facer, which belongs to the wet

end of the corrugator (Fig. 9). The earlier prepared adequate paper rolls uting and

liner are fed into the single facer, where the rst two board layers are sized.

Fluting,after being heated and passed under pressure between the uters,receives

the characteristic ute. The type of uters, i.e. the shape of utes thereon (of particu-

lar parameters such as ute pitch and height) is decisive for the type of the produced

corrugated board and its utility. Then, the peaks are thoroughly covered with a small

amount of the starch adhesive. In the next step the heated liner is sized with the uting.

Due to the pressure applied on papers while transferred between the pressure roller

and the uter, and in result of the temperature, generated by the rollers heated withsteam, adhesive joint binds the two papers. The single-faced corrugated board is the

product of this process. It is then used as a component for further processing or a nal

product. A single-faced corrugated board is a exible material which can be reeled, and

is the simplest product used for example as a protective wrapping or lining for various

surfaces and goods. Another important eld of application is the laminating process.

A diagram of the single facer is presented in Fig. 6, while Figures 7 and 8 present

respectively: a single facer with a pressure belt and with a pressure roll.


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Fig. 6. Single facer diagram

Fig. 7. Single facer with a pressure beltFig. 8.Single facer with a pressure roll

The next stage in the production of the corrugated board is sizing the second liner.

Single-faced corrugated board produced on a single facer travels along the special

bridge to the double facer. In this part of the corrugator glue is applied on the corru-

gated medium, and then the such prepared web of the single-faced corrugated board

leaves the wet end of the corrugator and is fed to the double facer, which belongs to

the dry end (Fig.10). At the same time the facing is fed under the corrugated board


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web. The process of nal bonding is carried out on the double facer. The corrugated

board web runs between the surface of the heated table and a movable pressure belt,

usually called a drying belt, where excessive moisture is evaporation (steam). Run-

ning through the double facer ensures also adequate setting if the adhesive joints.In order to produce a multi-faced corrugated board, the corrugator must be equip-

ped with several single facers two for the ve-ply board and three for the seven-layer

board.

Then the corrugated board goes to the cutter section. The rst stage is web lon -

gitudinal cutting. This is done on slitter scorer. The board web is cut perpendicularly

to the ute orientation into the required widths (sizes). Simultaneously the side edge

is trimmed in order to provide straight edges of the outer sheets (a trim is produced).

Creasing is also possible while longitudinal cutting (for future folds) of the board sheet.

The creased sheet is a component for the production of ap boxes. The next step is

the cross-cutting of the web, i.e. parallel to the ute orientation.

The section where this is done is called a sheeter. In most cases it contains two

(sometimes three) independent sets of rolls with cutting knives. This enables a simul-

taneous production of one, two or even three sizes of sheet from the same type of

corrugated board.

Fig. 9. Corrugator wet end


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Board sheets, which have been cut into the required sizes,are then transported by

belt conveyers to a machine piling them into evenly arranged stacks of the requested

number of sheets. Such prepared sheets may be piled on the pallets for immediate

sales or may be further processed into packagings.The most popular and applied corrugator equipment which provides value added

include:

preprint cutting systems enabling synchronous cross-cutting of the preprinted uting

webinthe designed position. The received printed board (usually with a multicolour

high quality imprint) is mainly used for high volume production,

tape application systems: tear-off, reinforcing and sealing tapes, which add new

functionalities to packagings made of the corrugated board. These include:quick and

easy opening, local break preventing reinforcement,e.g. handle reinforcement tapes,

or protection against an unauthorised opening,

coating systems for paper of board web: coating with waxes, lacquer, inks or other

preparations, which increase board resistance to moisture, grease and other substan-

ces.

Modern corrugators, which in production of double-faced corrugated board reach

speeds over 300 m/min, are equipped with automatic splicing systems. They are co-

Fig. 10. Corrugator Dry end


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upled with paper reel unwinders, and they allow for the reel change without stopping

or signicantly slowing down the machine; they also considerably reduce the amount

of scrap.

Moreover, the modern corrugators have additional systems improving their effec-tiveness and facilitating maintenance and control, which enhances the quality of the

product. The installed computer systems allow for a far reaching process automation,

ensure maximum reproducibility, reduce scrap and energy consumption. Frequently

they are interlinked with the integrated company management systems, which allows

to reach and exceed annual production capacities 100-200 mill. m2.


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Corrugated board packagings classication5.

Conversion is a term traditionally applied for a group of processes where the corru-

gated board is processed into packagings. Packagings made of the corrugated board

may be divided into different categories, depending on their construction, manufactu-ring process and application.

a. Classication according to the packaging construction

The most common packages made of corrugated board are ap boxes, also

known as traditional, American box, American standard, RSC (Regular Slotted Conta-

iner ) or FEFCO 201.

These are one-piece formed packagings, which may be produced of all types of cor-

rugated boards. They are manufactured on automated lines (inliners or exo folder glu-

ers), where in a singlepass of a properly prepared corrugated sheet the processes of

printing, cutting, folding, gluing and stacking are carried out. These packagings, thanks

to the application of the optional equipment, may be modied by using additional die

cut elements. Moreover, forming may be reinforced with staples or a tape. Flap packa-

gings may also be produced on simpler autonomous machines performing individual

operations. Such processes are less effective and more labour-intensive.

Another type of packagings are die cut boxes, also known as the shaped or so-

phisticated packagings. They are produced as sized packagings and as box blanks.

This group contains many various designs of closed packagings (boxes) and open

packagings (trays). These packagings form subsequent subgroups, according to their

lling, or manual or automated forming, etc. The common feature of this diversied

group is their manufacturing with a die.

A die is a tailor-made tool for a particular packaging. It is a laser-cut plywood, cove-

red with rubber dampers and ejectors, with slotting, creasing and perforating knives.

Such tool may carry out the complete processing of the corrugated sheet. Machinesproducing die cut packagings are called slotters.

Depending on the machine construction die cutting can be done on either at -

bed or rotary presses.


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b. FEFCO classication

There are several standard classications of packagings. Most frequently the FEF-

CO (European Federation of Corrugated Board Manufacturers) catalogue is used.

FEFCO code is a four-digit symbol, e.g. 0201, specifying the design of a packaging.FEFCO classication:

Commercial rolls and sheets (0100),

Slotted-type boxes (0200),

Telescope-type boxes (0300),

Folder-type boxes and trays (0400),

Slide-type boxes (0500),

Rigid-type boxes (0600),

Ready-glued cases (0700),

Interior tments (0900).

Commercial rolls and sheets are labelled with code 0100.

Fig. 11. Corrugated board sheets examples

Slotted-type boxes (code 0200) normally consist of one piece with a sized, stit-

ched or taped manufacturers joint and top and bottom aps.

Fig. 12. Slotted-type boxes examples


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Telescope-type boxes (code 0300) Telescope boxes usually consist of two or more

pieces and are characterized by a top piece (lid) tting over a bottom piece (bottom) or

both tting over a separate body.

Fig. 13. Telescope-type boxes examples

Folded-type boxes and trays (code 0400) Folding type boxes and trays usually

consist of only one piece of board. The bottom of the box is hinged to form two or all

side walls as well as the lid. Locking tabs, handles, display panels etc. can be incorpo-

rated in this design.

..

Fig. 14. Folded boxes and trays examples


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Sliding-type boxes (code 0500)consist of several pieces of liners and sleeves

sliding in different directions into each other. This group also includes outside sleeves

for other cases.

Fig. 15. Sliding-type boxes examples

Rigid boxes (code 0600)Rigid boxes normally consist of two side elements and a

middle part that is bottom as well as the lid in one . These boxes can be delivered as

individual units and have to be joined with the help of clamps.

Fig. 16. Rigid boxes examples

Ready glued boxes (code 0700) one piece telescope boxes which are shipped at

and ready to use by simple setting up. The boxes can be provided with a folding bottom

(folding bottom box) or with a diagonal bending (erectable box).

Fig. 17. Ready glued boxes examples


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Interiors (0900) such as inserts, dividers and partition walls can either be attached

to the box or loose elements. The number of elements are variable.

Fig. 19. Interiors examples

c. Special packagings SRP (Self Ready Packaging)

SRP (Shelf Ready Packaging)

SRP packagings are constructed to be used at shop shelves. Shelf ready packaging

has become an important element of the market game and a more and more frequently

used tool in brand marketing.

SRP must satisfy the following criteria:

easy identication which enables quick recognition of the content. The packa-

ging provides essential information necessary for the contained product: product

name, bar code, number of units, weight and validity. Thus the brand and theproduct are presented in transparent and orderly manner;

easy opening the SRP opening instruction should be placed in a visible place

and in a graphic form. Easy opening facilitates work of staff responsible for the

display of goods in a shop. No knife or other sharp tools are needed for opening

the packaging. It may also have handles or carrying holes;

easy shelf arrangement SRP have standardised dimensions, which are in

close correlation with the size of the rack where they are displayed. This allows

for an effective use of the shelf space, while the product arrangement process is

simple and easy. The SRP packaging even after a removal of part of its content

maintains stability and allows for an aesthetic display of the products;

easy sales an important feature of the SRP packaging is its aesthetics and

comfort. Packagings are designed to attract customer attention and encourage

people to buy the displayed products. They must not only protect the product,

but also perform the marketing function. The SRP packaging should also offer an

easy access to individual products, which in turn should build customer loyalty.


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easy disposal SRP packagings are also designed for an easy disposal. If

disposable, they are usually made of a single type of material. Often, the SRP

packagings are reusable.

Bag-in-Box

Bag-in-Box packagings are used in the food, pharmaceutical and household che-

mistry sectors, for packing uids and semi uids,mostly between 2 and 1000 litres.

Bag-in-Box consists of and inner packaging usually a multi-layer PE bag with a clo-

sure and an outer packaging a corrugated board box. These systems are used in the

food and industrial sectors, where the prolonged product validity and preservation is

essential.

Fig. 19. Bag-in-box examples


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Display and POS (Point of Sales)

Display or POS (Point of Sales) packagings play mainly marketing and display role.

Application of an effective construction combined with the attractive graphics increasesthe noticeability of the product at the point of sale.

Fig. 20. Display and POS examples


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6. Production process of corrugated board packagings

a. Production process of slotted-type boxes (RSC)

Machines for the production of slotted-type boxes (inliners or exo folder gluers) are

built of the modular sections, congured according to the expectations of individual

market segments, e.g. concerning the number of colours of an imprint or other modi-

cations of the ap box, such as carrying or ventilation holes, windows etc.

A typical construction of an inliners:

feeder is a section responsible for a synchronous feed of a board sheet into the

machine. In the machines with a common drive the main driving engine is also

located here. Often the feeder is preceded by the pre-feeder, i.e. a peripheral

device automatically passing sheets to the feeder. Pre-feeder allows for higher

productivity and eliminates the manual labour.

exographic printers. Usually there are several exo printers in the line. Each

may print a single colour. In order to obtain a multicolour imprint we need mi-

nimum three colours (Cyan, Magenta, Yellow). Printers in addition to inks may

also apply glossy, anti-gliding and other varnishes. For such application however,

subsequent units are needed. The main part of the machine is responsible for an

even ink distribution on the convex parts of the exo printing form, called a printing

matrix or a lm, which mounted on the printing cylinder. Printing forms are made

of photopolymers, which in the process of photo-mechanic-chemical processing

are mounted to the lm and the catches ensuring a secure and precise assembly

in the machine. During the rotation the lm meets the horizontally passing board

sheet, leaving an impression of the convex elements, while the concave parts

leave the remaining sheet unprinted. Anilox (a raster roller) is responsible for an

even distribution of ink on the lm. Anilox is usually covered with a ceramic layer

which is laser engraved. Anilox surface is a negative halftone screen with the

following parameters:- number of lines per 1 cm or 1 inch,

- raster angle,

- raster volume, cm3/m2.

Ink lls the raster ink carriers, while the excessive ink is removed by a rubber roller

doctor blades. Printer is equipped with ink unit responsible for the continuous ink circu-

lation during the work of the machine and a mechanical or under-pressure transporters

passing the board sheet through the printing process. All elements responsible for


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controlling the required parameters, such as pressure, parallelism or roller alignment,

have mechanical or computer controlled controls with independent drives.

Fig. 21. Diagram of the exographic printer with the ink and doctor blade chamber

Fig. 22. Diagram of a exographic printer with a rubber roller

slotter is a unit which slots the box blank in the corrugated board sheet using the

adjustable cutting and bending heads. Elements of this unit cut slots, glued aps

and crease the sheet crosswise.

rotary cutter is a unit which using a rotary cutting die, i.e. a tool specially develo-

ped for a particular packaging, may cut its subsequent elements. Such elements

include: handles, inclined or rounded corners of the closing aps, windows, easy

folding bottoms (envelope type) or the tear-off perforations.


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A die is a half-round plywood, with steel knives, rubbers and other special elements

for corrugated board converting and ensuring scrap ejection.

folder-gluer is a unit where the previously cut blank is folded and glued. A blank isfed to a spider with moving belts, where it is folded to a closed form. In the initialstep

of the folding process glue (polyvinyl acetate dispersion) is applied on the places to

be sized,by the gluer. Optionally the folder may be equipped with a stitching or taping

unit.

bundling unit, also called a counter or stacker, is responsible for piling the packa-

gings into the bundles. This is the nal section of the machine, synchronised with the

speed of the preceding units. It is followed by subsequent devices which bound the

bundles with tape in order to ensure stability and x glue joints. At the end there are

simple devices or robots for palletising.

Usually machines are linked to the internal handling system, which - using belt or

roll conveyers- deliver stacks of corrugated board to the machine and transport nal

products.

Modern machines have sophisticated control systems, which using computer

technology ensure repeatability of the subsequent runs of the same product, using

the data base of the machine.

Because of different machine size, machine name may be preceded by a prex:

mini, midi, maxi, and in case of the largest ones - jumbo.

Fig. 23. Machine for production of slotted-type boxes an inliner (FFG).


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b. Die-cut packaging production

Die-cut boxes are produced on the automated production lines, which due to the

cutting method are divided into at and rotary die cutters.Since the die-cut packagings may be delivered to customers both in the folded form

and as at blanks, the production process is additionally equipped with folder-gluers.

In the lines for manufacturing the die-cut boxes there are two primary types of ma-

chines: printers and cutters, which may work together (inline) or may operate indepen-

dently (ofine).

Printers

Flexo printers print on the board (post-print), which then is passed to the die cutters.

These machines have: a feeder, printing sections and a stacker. In order to secure high

quality and productivity of imprints, such machines are usually set as xed unmovable

printing sections. In the modern machines it is possible to set individual section when

the machine is running.

Moreover, the high quality printing (HQP) machines must be equipped with supple-

mentary devices, such as:

air or infrared dries for drying the printed surfaces,

underpressure transport unit with independent drives,

surface cleaning systems at the printer entry,

online quality control system, with cameras and scanners.

As an option, there may be systems for quick and automated anilox change, provi-

ding ink distribution required by a particular design.

Fig.24. An ofine Flexo printer


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Fig. 25. Inline Flexo printer

Flat die cutters

Flat die cutters use at dies, cut and bend board sheets, often offering several

blanks form a single sheet. The machine die-cuts the sheets by hitting a plated pressbelow a blanking die. Each die is dedicated to a particular product a packaging.

A blanking die in such machine is composed of the following components:

a proper cutting die, made of laser-cut plywood with the mounted cutting, bending

and perforating knives, covered with push-out and damper rubbers,

set of screws and handles for precise and quick mounting,

cleaning unit, called a striper. It is composed of two parts a top and a bottom one,

responsible for the removal of the inside and outside scrap of the blank (the outside

scrap appearing at all sides of the blank),

plywood, colloquially called a guillotine, slitting the frontal scrap.

Flat die cutting offers very high blank precision and repeatability,without signicant

quality drop with the die wear. This cutting technique allows for diversied and com -

plex packaging shapes, while the so called counter-crease provides precisely folding

blanks,for processing on customers folding automated machines. Flat die cutters are

also equipped with pre-feeders, breakers and separators of carton blanks.


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Fig. 26. Flat Bed Die Cutter

Rotary die cutters

These lines are usually composed of a feeder, printers and rotary die-cutters. Rotary

die cutting can cut larger blanks or more blanks than the at die-cutting, which results

in higher productivity and product exibility. However, this type of blanking has lower

sheet cutting precision (higher size tolerance), which to certain extent limits the subse-

quent use of automated folding machines.The section which is responsible for removing scrap from blanks is the cleaning sec-

tion, built of vibrating belts unit and brushes with blowers and exhausters Suchdesign

does not require any additional devices for blank cleaning.

The next unit is a blank stacker. There are two versions of stackers. In the rst option

blanks are directly formed into a stack, thus nalising the production process. In the

second option bundles of several dozens of blanks are formed, which then go to blank

separating unit,and are stacked.


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Fig. 27. Rotary Die Cutter - RDC


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Folder-gluers

Multipoint gluers

These machines have extended gluing and folding systems. This allows for gluingin one, two, three, four or greater number of points. Blanks are mostly made on at die

cutters and after passing the feeder they go to the folding unit. Here they are bended

and folded while glue is applied to appropriate areas. Folded boxes then go the pres-

sure unit, where - during a pass under the pressure belt (within a dozens of seconds)

- the glue joint is xed. Then the packagings are bundled (manually or automatically)

and stacked.

The multipoint gluers are usually used for the production of the three-point glued

boxes and four-point glued trays. These packagings are commonly used for mass

scale packaging process. Their construction and gluing method enable quick and easy

forming.

Single-point gluers

They are usually compact, semi-automated and built on a single machine frame,

and their task consists in gluing the blanks with cold and/or hot-setting adhesives. They

can also glue two parts of a packaging. This is particularly useful in case of large-size

boxes, which (due to the required dimensions) cannot be produced from a single board

sheet. A popular option is equipping the machines with a stitching and gluing unit or a

separator.

Fig. 28. A multipoint gluer


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Offset printing of packagings

Offset printing

Offset is a at printing technique, i.e. the printing and non-printing elements are atthe same height in relation to the plate. Image is transferred from the printing form to

the substrate with an intermediate cylinder covered with rubber, the so called printing

blanket.

There are two printing methods - web and sheet offset printing.

In case of the web offset paper is fed in reels, and the printing process may use

a heatset to x inks by penetration and evaporation of solvents. This enables printing

of coated papers.

Another option is the coldset,where ink is xed by paper penetration.

Web offset printing allows for perfecting, when web runs between two intermediate

rolls. Machines of this type are usually equipped with a unit for cutting and folding pa-

per into a folded sheet.

Typical nal products of the heatset machines are multi-colour magazines printed

on LWC or S.C. papers, while coldset is used for newspapers.

In the sheet offset - board sheets serve as printing base. It is one of the most

popular printing techniques, enabling accepting even very small orders. Usually the

sheet printing machines print one side of the paper, however a second paper pass is

also possible. Special equipment may also be installed, the so called perfector, which

enables automated sheet reversing and perfecting. Sheet is transferred by transport

suckers, which hold the leading edge carry the sheet along all printing units, up to the

sheet delivery section.

In offset a printing form, known as a plate, is a thin aluminium sheet with hydrophi-

lic elements damped with moistening agent, and hydrophobic or oleophilic elements,

damped with printing ink. Moistening solution is composed mainly of water and additi-

ves which decrease surface tension, as well as stabilizers, maintaining the adequate

range of the solutions pH. Isopropyl alcohol (IPA) a substance harmful both for the

environment and employees is an important component of the solution. Currently we

observe attempts to remove IPA by applying special eliminating buffers.


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First, a plate is damped with water, then with ink. There is a process of mutual repel-

lence of ink and the wetting agent. Ink remains only on the plates oleophilic areas and

with the intermediate cylinder - covered with a printing blanket - it is transferred onto

the printing base (that is why this technique is called indirect print).There also is a special variant of the technique called a dry offset, where a silicon

printing form is not damped with a moisturising solution. This method is applied mainly

on not absorbing substrates. In this manner, similarly to exography, a monochromatic

copy is produced by a single printing unit.

With high quality and possibility of reproducing images of high resolution, for multi-

colour images it is enough to use the four primary colours (the CMYK triad). Additional

colours are added in order to obtain effects exceeding the standard triad or special ef-

fects, e.g. metallic, reserved corporation colours, etc. Special effect may also be obtain

by application of UV inks xed by polymerisation initiated by UV rays. This method

enables printing of completely non-absorbing surfaces, such as plastics, lms, etc.

In offset printing it is also possible to apply high-gloss varnishes and other coatings

which improve aesthetics utility of a packaging. Varnish is applied on paper with a prin-

ting unit (oil-based varnishes) or with a varnishing tower (water-based varnishes and

UV), using a exographic print.

Fig. 29. Diagram of an offset printer

The dynamic development of this technique in the recent years results from the di-

gital image-setting, which reduces the time and improves the quality of the offset plate,

and consequently signicantly reduces the production costs.


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In the technique called CtP (Computer to Plate) image is transferred by the image-

setters directly onto the printing plate, and after image development the printing form is

ready. The CtP imagesetters are commonly used even in small printing plants, as the

low costs of imagesetting allow for short print runs.

Laminating

Insufcient compensation of uneven surface of the corrugated board during the of-

fset printing prevent application of the method for direct printing. Direct offset printing

is only possible on corrugated board with low ute height. However the packaging pro-

duction technology offers solutions which enable offset printing. Such commonly used

solution is lamination, i.e. pasting of the earlier printed paper sheet on the corrugated

board. The printed sheets of paper are xed to the board with glue, most frequently a

dispersion of polyvinyl acetate, on machines called laminators. The paper is glued to

the single-faced corrugated board in rolls, or to the sheets of board with three or more

plies. Subsequent stages of processing of the intermediate product depend on the

packaging design and are analogical to the post-printed slitting and/or die cutting of

the post-printed boxes.


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7. Major properties and parameters of corrugated board

a. Basis weight

Determination of basic weight is based on PN-ISO 536:1996 standard. It is a massof corrugated sheet of 1 square metre. It is expressed in [g/m2]. The area of a sample

sheet should not be smaller than 100 cm2and should not exceed 1000 cm2. This is

one of the basic characteristics of paper product (including the corrugated board).

Currently when more and more diversied papers are used, in order to specify board

quality it is necessary to test other parameters, e.g. ECT. Tolerance interval for basis

weight is 4%.

b. Edge crash test (ECT)

ECT test is performed in accordance with PN-EN ISO 3037:2000 standard. Undo-

ubtedly the edge crash resistance is one of the major characteristics of the corruga-

ted board. Edge crash strength is expressed in [kN/m]. In different parts of the globe

different ECT tests are carried out, however the most common is the below described

unwaxed edge method.

Testing principle: A rectangular sample of corrugated board (25 mm 0,5 mm paral-

lel to the utes and 100 mm (0,5 mm) perpendicular to the ute orientation) is placed

between two plates, and is put to cramping pressure test until the sample crashes.

Maximum pressure withstood by the sample is measured. This parameter is usually

an important additional characteristic presented in corrugated board specication in

commercial offers and in packaging specications. Tolerance interval - 10 %.

Fig. 30. ECT test


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c. Flat crash test (FCT)

The FCT test is carried out on the basis of PN-EN 23035:1999 standard. This me-

thod of testing at crash resistance is suitable for two or three-ply corrugated boards.It not used for board with more plies.

The testing method: A sample, cut of corrugated board, is subjected to increasing

pressure, applied perpendicularly to the surface, until the corrugated medium is cra-

shed. Maximum force withstood by the sample is measured.

Flat crash resistance is expressed in [kPa] (maximum pressure to the sample sur-

face).

Test results depend on the ute type and the corrugated medium properties. The

test is applicable wherever it is important to know the characteristics of this ply of the

corrugated board. Tolerance interval for this parameter is 10 %.

Fig. 31. FCT test

d. Bursting strength

Test is performed in accordance with PN-EN ISO 2759:2005 standard. Bursting

strength species the maximum pressure produced by the hydraulic system pushing

a rigidly clamped exible round diaphragm on the sample, causing its burst. Burstingstrength is expressed in [kPa].

The burst index is a ratio of board bursting strength to the basis weight of the bo-

ard, determined in accordance with ISO 536:1996


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Fig. 32.Burst test

This parameter is strongly dependent on paper type used for liners. Papers made

of primary bres have much higher burst index than the papers and boards made of

secondary bres (recovered paper). Tolerance interval is 10 %. Frequently, also the

minimum value is specied.

e. Puncture resistance test (PET)

The test is based on ISO 3036:1975 standard. The test consists in measuring the

energy required for an effective puncture of a board sample with a head, which should

be a triangular pyramid. This method is applicable to all types of corrugated board. The

sample should not be smaller than 175 mm x 175 mm. Puncture strength is expressed

in [J].

This test is a perfect tool for evaluation the risks a packing may be subject to in the

logistics chain. Tolerance interval for the parameters is 10 %.

f. 4-point bending stiffness

Test is carried out in accordance with ISO 5628:1995 standard. It species the ben-

ding moment per width unit, shown by the corrugated board when bended within thelimits of the elastic strain. The 4-point bending stiffness is expressed in Newton-metres

[N*m].

This is one of very few methods for measuring the deterioration of board strength in

the conversion process. Tolerance interval for the parameter is 10 %.


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Fig. 33. Bending stiffness test

g. Water absorption (the Cobb test)

The test is performed in accordance with PN-EN 20535:1996 standard. The test

allows for the evaluation of water absorption by the corrugated board. Mass of water

absorbed within a specied time by 1m2of board in specic conditions, is a measure

of water absorption in COBB units. The testing time depends on the type of board and

is within the range between 30 s 1800 s, while the result is presented with a time

index.

Fig. 34.Water absorption test

Water absorption determines applicability to a certain converting processes (e.g.

printing) and properties e.g. resistance to the changing atmospheric conditions. In

most cases the maximum acceptable parameter tolerance is specied. Usually it is

within 30-60 grams per square metre.


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h. Moisture content

Moisture content is tested in accordance with PN-EN ISO 287:2009 standard using

a chamber dryer. Moisture content in the board is specied as ratio of sample massreduction after drying to the initial sample mass, usually expressed in [%].

This is an essential parameter to measure. Moisture content of the corrugated bo-

ard translates directly onto its resistance properties and applicability to processing.It

inuences the dimensional stability of the board and packagings thereof. Tolerance

interval for the parameter is 2 %of the nominal value.

i. Flexion of corrugated board (atness)

Flexion is dened as the ratio of the sheet bend height (N) to the sheet length (L). It

is expressed in [%]. It should not exceed 4%.

Fig. 35. Corrugate board exion

where:

I= atness, %

Nmaximum bow heightmm

Lsheet length, mm (default 1 m)

This factor is particularly important in case of boxes (blanks) for machine packa-

ging.

j. Colour of corrugated board

The colour of the corrugated board is not unequivocally specied. It is assumed

as characteristic for paper products and should be the same at least within a single

production run.


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8. Major properties and parameters of packagings

Strength parameters

The basic and the most frequently used measure of strength of the corrugated bo-ard packaging is the box compression test (BCT).

The parameter is determined in order to measure the box resistance to loads cau-

sed by compression and stacking. The test consists in compressing a box between two

parallel plates, until the walls crash. Test is carried out on empty containers, after they

have been properly formed and glued. The resistance is tested for vertical, lateral and

longitudinal compression. Resistance level in case of the lateral and longitudinal com-

pression is not as high as for the vertical compression (PN EN ISO 12048:2002)

Fig. 36. BCT

Boxes made of the corrugated board should ensure an adequate protection of the

content during the entire cycle of packaging and distribution. The fullment of this task

depends on the quality of board used and the workmanship. The check-list presented

in Table 3 often serves as an example of a required specication.


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Item

numberParameter

1 Internal and external dimensions of a packaging

2

Packaging construction:

- Fefco no.

- according to the enclosed drawing

- according to the enclosed design

3 What is the product or the primary packaging and can they carry loads

4

Joining method

- glue

- stitching + gluing- stitching

- not applicable

5

Board type: 3- or 5-ply

- two-sides white

- one-side white

- two-side grey

6 Flute type

7 Weight of the packaging content

8 Number of layers on a pallet

9Are the pallets to be stored one on anther?

Yes/No

10Will the goods be stored in cold store?

Yes/No

11Pallet type

EURO/disposable

12May pallets jut out of the pallet?

Yes/No

Table 3. Check-list


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b. Other packaging tests

Applied for instance in case of special testing programmes applicable to packagings

for dangerous materials.Dangerous materials should be stored and transported in special quality packa-

gings, in order to withstand vibrations and loading operations during their transport.

Packagings should bemade and closed in a manner preventing any loss of their con-

tent in transport, due to vibrations, temperature changes, humidity or pressure. Each

dangerous material should be packed in such type of packaging which is certied by

an applicable packing instruction and stipulated in the relevant regulations.

The basic program of tests for certied packagings (legal requirement for dangerous

material packagings) include:

drop test,

horizontal impact,

static pressure.

c. Dimensioning

There are three types of packaging dimensions:

inside,

outside,

constructional.

Dimensions are always given in the following sequence: length, width, height and as

a standard they apply to the box interior. These are the inside utility dimensions.

Inside dimensions of a packaging (length and width) are distances between two

opposite walls of the formed box. Height is a distance between the inside aps forming

a bottom and the top (lid).

We should stress that measurements must be made in the nearest places (whichguarantees that the inside dimensions are at least equal to the dimensions of the pac-

ked product).

If other than the inside dimensions are given, it should be clearly and expressly

stated for example outside dimensions, which are the overall dimensions of the pac-

kaging.

Moreover there a constructional dimensions, which appear in designs (2D), sent for

the approval. This type of dimensioning does not include the material thickness and is

identical to the axis of the box constructional walls.


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Fig. 37. Box dimensioning

d. Tolerances resulting from the technical capacities of the converting machi-

nes

BCT tolerance 10% of the nominal value,

Inside dimensions tolerance 2 mm,

tear-off strip arrangement 2 mm,

crease spacing 2 mm,

shtail

Fig. 38. Fishtail

The term Fishtail is used for lack of parallelism between the edges on the joint side

/ at the glued ap.

Distance variations (K1-K2), presented in Figure 38, depend on the ute type and

should not exceed:


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- B ute: 4,5 mm,

- C-A ute: 6,5 mm,

- AB-CB ute: 8 mm.

Colour of packaging

For packagings with white liner it is possible to specify the whiteness. For the so cal-

led brown packagings colour is not specied and should be treated as characteristic

for the paper industry products. Possible colour variations are acceptable.

Volume tolerance number of packagings or sheets

A buyer should accept the delivered packagings or sheets, in accordance with the

following tolerances:

20% 4000 pieces of packagings or sheets.

Warranty

A warranty may cover one year both for packagings made of cellulose paper and of

recovered paper, calculated since the production date, excluding the imprint, subject

to keeping adequate storage and transport conditions.

6.


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9. Packaging, storage and transport standards for packagings

Packing

Supplies of packagings to external or customers warehouses should take into con-

sideration the climate and transport conditions, which may affect product quality (pac-

kaging, corrugated board).

Adequate pallets must be used for storage and transport of packagings. Packaging

must be placed on a dry pallet, protected with an additional sheet of board. Pallet he-

ight should be adjusted to the storage and transport requirements. A standard height of

goods with a pallet is in the range 1800 mm - 2200 mm, depending on the producers

and/or customers conditions.

In order to prevent draftage in transport, pallet tapes are used. In certain cases in

addition to tapes, it is also possible to use shrinkable pallet covers. Proper protection

of goods for transport is required for the maintaining of packaging quality.

Storage

In order to maintain the quality of packagings at a constant level, they should be sto-

red in accordance with the general recommendations for storage of corrugated board

packagings. The major recommendations include:

Storage of packagings in properly ventilated premises, where the temperature

and the relative humidity are respectively 530C and 30-70%. Rapid changes of

temperature or humidity in stores must be prevented;

Storage not directly on the oor but on pallets or platforms, on clean and dry

surface;

Protecting packaging against water (rain, condensation, leaks) and excessive di-

rect sun operation. Packagings must not be splashed with water when handled;

Protection against dust, which may be damaging for packing machines;

Protection against heat and rapid changes of climatic conditions (frequently ope-

ned doors, adverse effects of ventilation systems, etc.);

Ensuring appropriate movement of packagings the FIFO principle rst in / rst

out;

Maintaining packagings in the condition in which they arrived, without removing

protective devices until their release;

Rexing the protective lm and straps after part of the packagings were taken away

from the pallet. When rexing the wrapping, attention must be paid to avoid damaging


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the packagings. Damaged packagings may lose their functionality as well as they can

block lifting or packaging equipment;

Avoiding high vertical storage of pallets. In certain circumstances this may damage

packagings placed on the bottom pallet;Cautious use of sharp objects (knives, etc.) for opening pallets or wrapping removal.

This may damage the packagings;

Keeping all ID documents on the pallet until all the packagings are used.

Implementation of the above recommendations has a positive impact on the utility

of the products.

Transport

Adequate transport of the board packagings to an external store signicantly affects

their quality. There are the following types transport:

road transport,

by rail,

by water (inland water or by sea),

by air.

Safeguard should be adjusted to the type of transport. In case of road transport of

carriage by rail or by air, special attention should be paid to protection against mecha-

nical damages. In water transport there is an additional risk resulting from humid air

and wetting of packaging. Also the cleanness of means of transportation is important

(odour, dust).

In all the above mentioned cases we should apply exactly the same safeguards as

in storage.


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10. General introduction to standards for corrugated board packaging

used for food

There are not any specic directives or binding regulations on the EU single market,which are applicable to packagings made of corrugated board and which are used in

direct contact with food (at least until the publication of this paper). Producers of such

packagings may apply standards related to food safety. Thus, for the production of

packagings made of the corrugated board and intended to come into contact with food,

it is recommended to apply one or several of the following standards:

GMP and GHP,

HACCP,

PN-EN ISO 22000:2006 with additional specication PAS 223:2011

BRC, particularly chapter Global Standards for Packaging and Packaging Mate-

rials, 2011

IFS.

a. GMP (Good Manufacturing Practice) and GHP (Good Hygienic Practice)

GMP/GHP book contains a set of guidelines on good manufacturing and hygienic

practice. It has been based on:

Guidelines of the World Health Organisation of Codex Alimentarius,

Regulation (EC) No. 1935/2004 of the European Parliament and of the Council

of 27 October 2004 on materials and articles intended to come into contact with

food,

Regulation (EC) 2023/2006 of the Commission of 22 December 2006 on good

manufacturing practice for materials and articles intended to come into contact

with food,

Regulation (EC) No 178/2002 of the European Parliament and of the Council of

28 January 2002 laying down the general principles and requirements of foodlaw, establishing the European Food Safety Authority and laying down procedu-

res in matters of food safety,

Regulation (EC) No 852/2004 of the European Parliament and of the Council of

29 April 2004 on the hygiene of foodstuffs.

It is suggested that GMP should be adopted as the recommended standards to be

also applied by the manufacturers of packagings made of the corrugated board. In

particular, GMP contains guidelines concerning the following issues:


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plant location,

buildings, constructions, production, storage and communication facilities,

plant, equipment, accessories,

raw material supplies

corbro general issues and the recommended standards

Documents